Train dispatching system for railroads



Y o. H. DlcKE TRAIN DISPATCHING SYSTEM FOR RAILROADS Sept. 8, 1931.

IN NToR CU my 'TRNEY Filed April 15, 1927 y... LD

lllIL Patented fSept. 8V, 11931Ky UNITED STATES PATENT OFFICE OSCAR H. DICKE, OF ROCHESTER, NEW YORK, ASSIGNOR' TO GENERAL RAILWAY SIGNAL COMPANY, 0F ROCHESTER, NEW YORK TRAIN DISPATCHING SYSTEM FOR RAILROAIDS Application filed April 15,

This invention relates to train dispatching systems of the Wayside signal indicating type, and more particularly to means for OS-ing the conditions of traflic of such systems.

The term OS-ing is used by railway signal engineers to denote the report of a train location or passage with respectto a certain point on a railway system and this term is used herein to signify the indication automatically transmitted to a dispatchers oiiice as to the condition of occupancy of a certain track circuit or group of track circuits. In order to economically indicate at a dispatchers office the condition of occupancy of a large number of track circuits, it is necessary to transmit the indicating conditions as to occupancy of a large number of such track circuits over a single medium, such as a single line circuit. The chief problem that presents itself in this connection centers around the fact that not only is it possible that several track circuits will be entered upon by diiferent trains at exactly the same time, but that such coincidence is quite probable. In view of this fact, it is not practicable to transmit a large number of OS signals over the same line wire by distinctive codes, as they are ordinarily understood, because if two trains would enter different track circuits at about the same time a jumbled up code, or series of impulses, the meaning of which could not be deciphered, would be transmitted.

In view of the above and other important considerations, it is proposed in accordance with the present invention to use a single line circuit for transmitting OS signals to indicate the occupancy of a large number of track circuits, and indicate other local con. ditions, such as, positions of track switches, indicating conditions of signals and the position of drawbridges, derails and the like, by transmitting distinctive frequencies from these points over such line circuit to dis- 1927. Serial No. 184,013.

tinctive frequency responsive relays or indicaters.

In order to make it possible to transmit an extremely large numberof disf cations may be transmitted over the same` line circuit. e

Other objects, purposes and character`- istic features of the invention will in part be apparent from the drawings, and in part be pointed out in the specification hereinafter.

In describing the invention in detail, reference will be made to the accompanying drawings in which:-

Fig. l shows a portion of a railway track lay-out illustrating a single track and` a passing siding, together with a dispatchers tower in which indicators embodying the present invention corresponding to the track relays shown at such passing siding have been illustrated in a immature track layout;

Fig. 2 shows a plan or front view of the panel of the miniature track layout illus'- trating an indicator of the mechanically tuned reed type forming a part of the equipment in the dispatchers ofce;

Fig. 3 Vis a partial sectional view of thev indicator shown in Fig. 2 taken on the line 3 3, as viewed in the direction of the arrows of Fig. 2;

Fig. 4 illustrates a combined transformer and interrupter for changing direct (',ul'rel'ltv into alternating current of a predetermined frequency and for inducing a voltage of such frequency in an insulated coil contained in a line circuit; and

Fig. 5 shows a modified form of the inven-i tion in which a vibratory reed is adapted to close an energizing circuit for an indicating lamp.

Referring to Fig. 1 of the drawings the dotted rectangle DO conventionally indicates a dispatchers ofiice in which is contained suitable control apparatus for operating the switch machines and signals at a number of dist-ant passing sidings of a railway system, which apparatus has not been specifically shown, but of which the control levers LE and LV have been indicated in this dispatchers tower DO. The switch machines SMvV and SME conventionally shown are used for operating the track switches STS and 1TS, and are controlled by suitable control circuits conventionally illustrated by dotted lines 6 and 9 in accordance with the energized condition of the control relays ZW and ZE respectively; and these control relays ZW and ZE are controlled from the dispatchers ofiice DO by any suit-able means, which has been conventionally shown by the dotted lines 40 and 41, all as more specifically shown in my prior application Ser. No. 180,475 tiled April 2, 19277 or as shown in the application of S. N. Wight Ser. No. 120,423 filed July 3, 1926.

In this dispatchers tower is contained a miniature track layout, preferably suitably ingraved on a large panel 10, having holes therein through which the ends of the tuned reeds of the various track circuit indicators project, the location of each indicator' corresponding to that of the track circuit controlling the same. In the particular arrangement shown only six such indicators have been illustrated, which indicators have been designated 7l, TDI, 1I, 81, 2DI and 2l.

Each of these indicators comprises a U- shaped core 11 constructed of laminated transformer iron, to which core is suitably secured, as by a screw 12, a reed 13; and on this core is contained a coil or winding 14 which has a condenser C connected thereacross, which condenser electrically resonates the winding 14 to the same frequency as the natural period of vibration of the reed 13. This core 11 is secured to the back of the panel 10 in any suitable manner as by the screws 15 shown. The reed 13 is preferably made of permanent magnet steel and preferably has a spring 13a for properly tuning this reed suitably riveted thereto. .This reed 18 is preferably magnetized, so that it is attracted when current flows in one direction and repelled when current flows in the opposite direction.

The particular distant passing siding illustrated in Fig. 1, is one in which a sutcient number of signals have been provided for controlling the entrance and departure of trains into and out of both ends thereof. In the particular arrangement shown the west end of the siding has its track rails insulated by insulating joints 2O so as to form a detector or fouling track circuit including the detector track relay IDT and the track battery 21; and at east end of this passing siding in a similar way has the track rails insulated by insulating joints 23, so as to form another detector track circuit which includes the detector track relay 2DT and the track battery 24. The main track of the passing siding is provided with a track circuit including track relay 1T, and a track battery 25; and the side track of the passing siding is track circuited and includes a track relay 8T and a track battery 26. At the east end of the passing siding are two starting signals 2 and 2D which govern the movenient of the trailic out of the assing siding into the single track section 1n an easterly direction, and at this same end is provided a main entrance signal 1 and a take siding signal 1D. In the same way, the s'Larting signals at the west end of the passing siding have been designated *.7 and 7D respectively, and the main entering signal has been designated 8 and the take siding signal has been designated 8D. These various signals are preferably jointly controlled in accordance with traffic conditions ahead and in accorciance with the normal or reverse energized or the deenergized conditions of the control relays ZlV and ZE, which control relays are controlled by the dispatcher as already menf tioned. Although no specificV circuits for controlling' these signals at the west and east end have been shown it is desired to be understood that they may be controlled in a manner as shown in either of the two prior applications heretofore referred to and as conventionally shown by the dotted lines 3G and 37, respectively. These lines have been shown including the swich machines SMV and SUE to signify that the position a particular switch machine is assuming determines whether or not a particular signal shall be permitted to clear when traffic conditions ahead of such signal are clear.

Although the distinctive frequencies for operating the various distinctively tuned reed type relays or indicators shown may be obtained from generators of the usual construction, it is deemed more expedient to obtain these frequencies from tuned interrupters each of which is tuned to correspond to the tuning of the selective frequency responsive relay in the tower for which it is to generate alternating current. Referring to Fig. 4 a combined' interrupter and transformer for obtaining a distinctive frequency has been shown. This device comprises a closed core 30, constructed of laminated transformer iron containing a primary winding P and a secondary winding S. This coil 30 is provided with 2 projecting legs 30L and 30h, to the leg 30a of which is fastened the tuned armature 3l.

This armature 3l is Vsupported by a spring 32 secured to the leg 30 in any suitable manner, as by screws 33. A Contact spring 34 is riveted to the armature 3l in such a manner that the contact spring normally engages the stationary contact 35, illustrated conventionally in the form of an arrow. The stiffness ot the springs 32 and 34 and the weight of thek armature 3l are fsuch, that the natural period oi vibration of the armature corresponds to the natural periods of vibration of the indicating relay which the particular interrupter is intended to operate by supplying current thereto. .iThe armature 3l is preferably constructed of soft iron, and in this respect is different from the timed reed 13 of the indicator for which it is to generate alternating current, in that the tuned reed 1S preferably coinprises a permanent magnet. It may be pointed out in this connection that if the reed 13 ot the indicating` device were con structed of soft iron it would be attracted twice for each cycle of alternating current,

' "and for this reason it would not respond unless the natural period oi vibration of the armature of the indicator were twice that oi" the natural period ot vibration ot the armature of the corresponding interi rupter. Since, however, the interruptor in practice is supplied with direct current the armature 3l of such interrupter may constitute either a permanent magnet or a piece of soft iron.

Although the various indicators and interrupters shown in Fig. l of the drawings may be grouped in series or in multiple, or in any combination of series and multiple groups, all of these indicators and interrupters have for convenience been shown connected in series in a circuit which may be traced as follows :Hbeginning at the winding of the indicator SI, wire 43, winding of the indicator 7I, wire fle, winding of the indicator 7DI, Wire 45, winding of the indicator 1I, wire 46, winding of the indicator QDI, wire 4:7, winding of the indicator QI, wire 48, secondary winding S of the interrupter 7B, wire 49, secondary winding S of the interrupter TDR, wire 50, secondary winding S of the interrupter 1R, wire 5l, secondary winding S of the interrupter Slt, Wire 52, secondary winding S of the interrupter QDT, wire 53, secondary winding S of the interrupter 2R, wire 54 to the common return wire C, wire 55, back to the coil of the indicator SI.

Since, as was heretofore pointed out each of the various indicators and its corresponding interrupter, having` the same preiX number, have their reeds tuned to the saine natural period of vibration, and since the winding of each indicator has a condenser connected in multiple therewith of a capacityl so that its winding is electrically tuned to a potential resonance of the same frequency as the period of vibration of its series in the same line circuit and may eiy ther separately or in groups operating in overlapped relation distinctly indicate whether their respective interrupters are operating or not.

In this connection it may be pointed out that by reason of this timing oi the coil of each indicator the control current flowing in such winding predolninates over all other currents flowing therein, so that, not only does the reed respond because the control current falls in step with its vibration but 'further because this control current is greater in value. Also, since the amplitude of vibration is cumulative, when current of the proper 'frequency flows in the coil of an indicator, the frequency ot the current being in step with the. vibration of the reed, the spring 32 can be made stii'l enough so that the associated varmature will not be materially attracted by current oit another trequency flowing in such coil, and this is done in practice. Further, the impedancesl of the secondary coils S ot the various induction coils is so low that all of the various frequencies of current can readily flow therethrough.

Instead ot' giving a plurality of distinctive indications over the same circuit by having the operator observe which reeds are vibrating at an appreciable amplitude, a more arrestive indicationmay be given by the provision. of circuit closing means which either intermittently or continuously closes a circuit so long as the associated reed is vibrating` atan amplitude oi" a predetermined degree. In Fig. 5 of the drawing an arrangement of this kind has been illustrated in which the reed 13b has a spring contact linger riveted thereto, which contact upon vibration of this reed 13b to a predetermined amplitude will engage the stationary contact 66 illustrated in the torni oi' an arrow, and effect illumination oi the lamp 67 by completing a circuit connected to the terminals B and C of a suitable source of energy. Suitable audible signalingl means, such'as disclosed in my prior application above referred to, also may, if desired, be employed for calling the train dispatchers attention to a change in the status of train locations and the OS indicators visually indicating such locations.

In the particular arrangement shown, see ior instance the circuit for the inter` rupter 2ER, the secondary coil S of such interrupter is normally shun ted by the front `contact 57 oi the track relay QDT controlling lli! the same, so that th-e impedances of the coils S of such interruptor-s are normally not contained in the line circuit. Referring now to the track relay ST which controls the.

interrupter SR, this track relay 8T is deenergized, as shown in the drawings, because there is a train G0, shown conventionally, occupying the siding and the track circuit containing tl is relay 8T. With the relay 8T (le-energized the back contact 6l of this relay closes a circuit for the primary winding P of the interrupter SR. The llow of curr-ent in this circuit will instantly attract the armature 3l and thereby open the circuit at the contacts 2li-35, so that the armature 3l is again magnetically released to again complete this circuit. Repeated attractions of this kind will, of course, cause the armature 3l to vibrate in accordance with the natural period of vibration thereof, and will cause an alternating current voltage to be generated in the secondary winding S thereof, which will cause the tlow of current of a frequency which will ribrate the arniat 13 of the indicator' SI, such vibration being conventionally illustratcd by the multiplicity of reed ends shown in the opening of the indicator' SI in the dispz'.tchei"s oiice D0. In this same way any number of these indicators shown in the oilice D@ may be vibrated if currents of the proper distinctive frequencies flow simultaneously in the line circuit heretofore traced. .-'ilthough the various secondary windings Si have been shown normally shunted by contacts :57, it is desired to be understood that this feature is not essential to the working of the system, and that these contacts 5.7 may be omitted, if desired.

In view of the fact that train GO has been shown, and that the manner in which the presence of this train is indicated to the dispatcher in the tower D() by vibration of the reed of indicator SI has been pointed out, it is deemed unnecessary to dcscribe the operation of the system. however, be pointed out briefly how trains may be dispatched over the railway system in a general way. For instance, let us assume that the di )atelier wishes this train 6() to proceed in an easterly direction, he will incre the lever Ill@ to the left hand position thereby operating the switch inachine Slillll to the siding position through the medium of the control relay all in a manner as described in my prior application. vWith the control relay ZE energized to the take siding position and the switch machine SME operated to the take siding position the dwarf signal 2D will clear if tratlic conditions in advance are clear, and the train G0 may proceed easterly into the single track section. The dispatcher' at the tower will observe the indicators SI, QDI and QI and as these indica- It may, Y

Leashes i tors will be vibrated in succession but in overlapped relation,` the dispatcher is informed as to the progress of the train. Although only a limited number of indicators have been shown, it is desired to be understood that the occupancy of any and all track circuits of the railway system may be indicated by such indicators, and that the indicators may also be used for indicating the positions the switch machine SME and SM1/i7 are assuming at any particular time. Although only one passing siding of a railway system has been shown in the drawings and means for indicating occupancy or non-occupancy of the track circuits thereof has been shown, it is desired to be understood that in practice the same idea may, if desired, be applied to all the track circuits of the various sidings and the single track sections connecting the same, so that the train dispatcher is always informed as to the location and progress of trains under his control.

Having thus shown and described a rather specific embodiment of the present invention, and` having shown certain portions thereof rather specilically and having shown other parts conventionally, it is desired to be understood that the particular devices illustrated and the particular circuit arrangement in which they have been shown have been selected for the purpose of describing the invention rather than showing the scope thereof or the specific construction preferably employed in practicing the invention; and it is further desired to e understood that various changes, moditications and additions may be made to adapt the invention to the particular problems encountered in practicing the invention all without departing from the spirit or scope of the invention or the idea of means underlying the saine, except as demanded by the scope of the following claims.

1What I claim is 1. In a train dispatching system, the come bination with a railway track divided into a plurality of track sections by insulating joints, a track circuit for each section including a source of energy and a track relay, a local train dispatchers oilice, a plurality of indicators at said oiiice each responsive to alternating current having a frequency distinctive from the frequency any other indifator will respond to, a line circuit, a source of alternating current of distinctive frequency at each track section location, and

ieans for feeding alternating current from any one of said sources into said line circuit for rendering the corresponding one of said indicators responsive.

2. In a train dispatching system, the combination with a railway track divided into a plurality of track sections by insulating joints, a track circuit for each section including a source of energy and a track relay, a local train dispatchers oilice, a miniature track lay-out in said oliice, a selective frequency responsive indicator for each of said track relays located with respect to said miniature track lay-out in the same way as the corresponding track circuit is associated with said railway track, a source of alternating current at each track relay of a frequency the same as that to which the cor` responding indicator at the oilice will respond, and a single line circuit 'for connecting all of said indicators and all of said sources of alternating current.

3. In a train dispatching system, the combination with a railway track divided into a plurality of track sections by insulating joints, a track circuit 'for each section iiicluding a source of energy and a track relay, a local train dispatchers ollice, a miniature track lay-out in said oliice, a selective frequency responsive indicator for each of said track relays, located with respect to said miniature track lay-out in the same way as the corresponding track circuit associated with said railway track, a source of alternating current at each track relay of a frequency the saine as that to which the corresponding indicator at the dispatchers otice will respond, a single line circuit to which all of said indicators are connected, and means for connecting the source of alternating current located at a particular track relay to said line circuit when said track relay assumes a certain condition.

4. In a train dispatching system, the combination with a railway track divided into a plurality of track sections by insulating joints, a track circuit for each section including a source of energy and a track relay, a local train dispatch-ers ollice, an indicating device in said ollice including a mechanically tuned reed and a coil for electro-inagnetical ly vibrating said reed of lwhich the reed is mechanically and the coil is electrically tuned to the saine frequency, and means for energizing the coil of said indicator by an alternating current source of the same lirequency and located at said track relay when one of said sections is occupied.

5. In a train dispatching system, the combination with a. railway track divided into a plurality of track sections by insulating joints, a track circuit for each section including a source of current and a track re! lay, a local train dispatchers oce, a plurality of indicating devices in said oilice each including a mechanically tuned reed and a coil for electro-magnetically vibrating said reed, of each device of which the reed is mechanically tuned to a certain frequency and the coil is electrically timed to the saine frequency, and a tuned reed vibratory interrupter associated with each one of said track sections for generating an alternating current of the proper frequency for the corresponding indicating device and supplying said current to all of said indicating devices when said one track `section is occupied, whereby only the corresponding indicatingy device is rendered active in response to the transmission of one of vsaid frequencies.

` 6. ln a train dispatching system, the combination wit-li a railway track divided intov i a plurality ot track sections by insulating joints, a track circuit for each section including track relay and a source of cur renta local-dispatchers olice, an indicator for each ol said sections located in said oilice,^

distinctive frequency generating means for each of said sections all connected in series in a ci 1cuit including said indicators, and means associated with each section for normally shunting the corresponding generat ing means and for removing such shunt and rendering such generating means active when such section is occupied by a train.

7. In a train dispatching system, the combination with a railway track divided intoAVM a plurality of track sections by insulating" joints, a track circuit for each section including a track relay and a source of current, a local dispatchers office, an indicator tor each of said sections located. in said olice connected in series and eaclituned to po! tential resonance to a particular frequency, distinctive frequency generating means for each of said sections all connected in series in a circuit including said indicators, and.`A means associated with each section for nor` joints, a track circuit for each section in! cluding a track relay and a source of current, a local dispatchers oiiice, and indicator for each of said sections located in said office connected in series and each comprising a coil tuned to potential resonance for a particular .frequency and a reed mechanicallyr, timed to the saine frequency, distinctive frequency generating means for each of said sections all connected in series in a circuit including said indicators, and means assogciated with each section for normally shunt-` ing the corresponding generating means,

and for removing such shunt and rendering such generating means active when such section is occupied by a train.

9. In a train dispatching system, the com- ,c bination with a railway track divided into`- a plurality of track sections by insulating joints, a track circuit for each section including a source of energy and a track relay, a local train dispatchers otice, a miniature track lay-out in said office, a tuned reed indicator for each of said track relays located With respect to said miniature track lay-out in the saine Way as the corresponding track circuit is associated with said rail- Way track, a source of alternating current at each track relay of a frequency the saine 'Y as that to which the corresponding indicator Y at the oiiice will respond7 and a single line circuit for connecting all of said indicators and all of said sources of alternating current.

In testimony whereof I aiix my signature. OSCAR H. DICKE. 

